Rhynchosia ravii K. Prasad & A. Narayana Swamy, 2014

Prasad, K. & Swamy, A. Narayana, 2014, Rhynchosia ravii (Leguminosae-Papilionoideae), a new species from Andhra Pradesh, India, Phytotaxa 175 (3), pp. 155-160 : 156-159

Rhynchosia ravii K. Prasad & A. Narayana Swamy , sp. nov. ( Fig. 1 & 2 )

Type:— INDIA. Andhra Pradesh: Anantapuram district, Talapula forest , 550 m, 17 January 2012, A. Narayana Swamy & K. Prasad 38496 (holotype BSID!, isotypes SKU!)

Diagnosis: Rhynchosia ravii is closely allied to Rhynchosia beddomei , but differs in the following characters: plants with glandular hairs (versus glandular hairs absent); stipels present (versus stipels absent); racemes 5–6 cm long, laxlyflowered (versus racemes ca. 2 cm long, densely flowered); bracts ovate, deeply or shallowly 3-lobed (versus bracts cordate or oblong-ovate, acute or obtuse); calyx tube 2–4 mm long (versus calyx tube less the 2 mm long); gynoecium as long as or longer than the staminal sheath (versus gynoecium shorter than the staminal sheath); ovary ca. 4 mm long (versus ovary ca. 1.5 mm long); style ca. 6 mm long (versus style ca. 1.5 mm long); and fruits oblong, two seeded (versus suborbicular, one seeded fruits)

Erect shrubs, ca. 1.2 m high, with glandular tipped hairs, and with glands in the leaves; branches erect; mature branches woody, terete, tomentose or pubescent; young branches slender, terete, pale golden-yellow or greyish-white pubescent. Leaves 6–10 cm long, alternate, 3-foliolate; petiole ca. 3.5 cm long, with pale golden-yellow hairs; stipule oblong-lanceolate or ovate-lanceolate, 3.5–5 × 1–1.5 mm, acuminate, with dense greyish-white hairs, caducous; leaflets dimorphic, with dense, short, fine, greyish-white hairs canescent on both sides, veins impressed above, strongly raised beneath; terminal leaflet ovate-oblong or ovate-elliptic, ca. 5 × 2 cm, acute at apex, obtuse or cuneate at base, entire, petiolule 8–10 mm long; lateral leaflets obliquely oblong-ovate or oblong-lanceolate, ca. 4 × 1.8 cm, acute at apex, cuneate or obtuse at base, entire and slightly incurved at margins, petiolule ca. 2 mm long; stipels 2 per leaf, linear or subulate, ca. 1 × 0.4 mm, caducous. Inflorescence an axillary raceme, 1- 3 racemes per axil, slender, filiform, goldenyellow pubescent; peduncle terete, 1 - 3.5 cm long; racemes 5–6 cm long, laxly 6-8-flowered. Bracts ovate, ca. 5 × 2.6 mm, shallowly or deeply 3-lobed at apex, pubescent; bracteoles absent. Pedicels short, filiform, ca. 1.2 mm long, sparsely golden-yellow hairy. Flowers solitary, ca. 1 cm long, zygomorphic. Calyx pale green with pale rose tinge, ca. 1 cm long, campanulate, tube 2–4 mm long, with dense, short, fine, greyish-white hairs; lobes unequal, obliquely oblong-ovate or oblong-lanceolate, 6–8 × 4–4.5 mm, acute, 1-3-veined. Corolla standard yellow, orbicular, 7–8 × 7–7.5 mm, rounded and emarginate at apex, with two inflexed auricles at the base; claw 1.6–2 mm long; wings yellow, oblong or narrowly oblong-obovate, 7.5–8.2 × 2–2.5 mm, rounded at apex, without auricles; claw ca. 2 mm long; keels pale greenish-yellow or white, incurved, connate, falcately obovate, 7–7.5 × 2.6–3 mm, rounded at apex, with or without auricles; claw ca. 2 mm long. Stamens 10, white, diadelphous, 9 + 1, unequal; bundle 6–8 × 1.2–1.8 mm; individual filament ca. 7.5 mm long; anthers yellow, dehiscent, oblong, ca. 1 × 0.6 mm. Ovary sessile, oblong-elliptic, ca. 4 × 1.5 mm, with white hairs; ovule 2; style ca. 6 mm long, glabrous; stigma pale yellow, capitate, ca. 0.2 mm long. Pod compressed, longer than the calyx, septate between the seeds, oblong, ca. 1.4 × 0.7 cm, incurved beak, tomentose; seeds 2, subreniform, ca. 4 × 3 mm, strophiolate.

Phenology: November–April (flowering and fruiting)

Habitat: In red soils in grass dominated slopes of degraded dry deciduous open forests, at an elevation of 400–600m

Distribution: Anantapuram and Kadapa districts (Map 1).

Etymology: The new species named in honour of Dr. B. Ravi Prasad Rao, Professor of Botany at Sri Krishnadevaraya University, Anantapuram, India for his contributions to the flora of Andhra Pradesh, Eastern Ghats and Andaman Islands.

Conservation status: Rhynchosia ravii has a restricted distribution in Anantapuram and Kadapa district and the habitat is prone to seasonal anthropogenic forest fires, and grazing. According to our observations over 3 years, regeneration of the species is poor. Its extent of occurrence (EOO) is about 50 km 2 and area of occupancy (AOO) is less than 1 km 2. Based on the distribution, and on the observed threats to the populations and apparently low recruitment rate, we can provide a preliminary assessment of the species as Critically Endangered B1ab(iii, v) + 2ab(iii, v) following IUCN Version 11 ( IUCN Standards and Petitions Subcommittee, 2014). For a full assessment to be possible, further details are required of the biology of the species and threats to the populations.

Additional specimens examined: INDIA. Andhra Pradesh: Anantapuram district, Batrepalli forest , 500–550 m, 13 March 2011, B.R.P. Rao & A. Narayana Swamy 36627 ( BSID) ; Andhra Pradesh: Anantapuram district, Talapula forest , 550 m, 10 th February 2014, A. Narayana Swamy & K. Prasad 44908 ( SKU) ; Kadapa district , Mangapatnam forest , 550 m, 1 st December 2009, B.R.P. Rao & Prasad 41602 ( SKU) .

Discussion: Rhynchosia ravii is closely allied to R. beddomei but differs in the characters presented in Table 1.

MAP 1. Distribution map of Rhynchosia ravii , showing the localities in Anantapuram and Kadapa districts of Andhra Pradesh state.

Figures

FIGURE 1. Rhynchosia ravii. (A) twig (B) calyx opened out (C) bracts (D) standard petal (E) wings (F) keels (G) androecium (H) staminal column opened out (I) gynoecium (J) fruit (K) seed (Artist: K. Prasad. Drawn from the holotype, A. Narayana Swamy & K. Prasad 38496)

FIGURE 2. Rhynchosia ravii. (A) habit, (B) stem with glandular hairs, (C) leaf upper surface, (D) leaf lower surface, (E) stipels, (F) bract, (G) racemes, (H) flower, (I) calyx, (J) young fruit, (K) mature fruit, (L) young seeds, (M) mature seeds (Photographer: K. Prasad).